EVENT 334 Women Open 400m IM - Heats
| Heat Number - 1 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 1 | Jennifer Davis | 15 | Dunstable | 5:35.11 |
| 2 | 3 | Lyla Howard | 15 | Team Luton | 5:31.90 |
| 3 | 5 | Lucinda Stanley | 18 | Harpenden | 5:28.00 |
| 4 | 7 | Lexie Goodman | 15 | Basildon Ph | 5:27.66 |
| 5 | 6 | Amy Boreham | 16 | Watford SC | 5:27.93 |
| 6 | 4 | Isabelle Barber | 16 | Stowmarket | 5:28.92 |
| 7 | 2 | Amy Harper | 15 | Watford SC | 5:32.60 |
| Heat Number - 2 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 9 | Hollie Hawkins | 15 | Basildon Ph | 5:25.18 |
| 2 | 11 | Elise Delapperall | 16 | Thurrock | 5:24.31 |
| 3 | 13 | Molly Grieve | 17 | Colchester | 5:22.50 |
| 4 | 15 | Isabella Porzio | 18 | Putteridge | 5:20.00 |
| 5 | 14 | Macy Dexter | 16 | Co Cambridge | 5:22.10 |
| 6 | 12 | Romilly Marks | 16 | Newmarket | 5:23.52 |
| 7 | 10 | Molly Monk | 18 | Co Norwich | 5:24.60 |
| 8 | 8 | Anna Fallon | 19 | Team Luton | 5:27.59 |
| Heat Number - 3 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 17 | Olivia Newman-Baronius | 16 | Putteridge | 5:17.40 |
| 2 | 19 | Charlotte Tree | 18 | Colchester | 5:13.89 |
| 3 | 21 | Mia Lowe | 15 | Basildon Ph | 5:12.39 |
| 4 | 23 | Lexie O'Connor | 15 | Basildon Ph | 5:10.71 |
| 5 | 22 | Lilly Davis | 15 | Co Peterboro | 5:12.17 |
| 6 | 20 | Megan Pye | 20 | Co Norwich | 5:13.60 |
| 7 | 18 | Katie Andrews | 18 | Norwich Swan | 5:14.60 |
| 8 | 16 | Francesca Key | 17 | Thurrock | 5:18.82 |
| Heat Number - 4 |
| Lane | Comp.No. | Name | AaD | Club | Time |
| 1 | 25 | Charlotte White | 17 | West Suffolk | 5:06.45 |
| 2 | 27 | Cait Cotter | 15 | Chelmsford | 5:00.27 |
| 3 | 29 | Matilda Ransome | 16 | Co Cambridge | 4:58.10 |
| 4 | 31 | Ellie O'Keeffe | 22 | Co Cambridge | 4:56.61 |
| 5 | 30 | Natalie Sanford | 18 | St Felix Sch | 4:56.71 |
| 6 | 28 | Harriet Salisbury | 18 | Co Peterboro | 5:00.09 |
| 7 | 26 | Skye Carter | 15 | Basildon Ph | 5:02.28 |
| 8 | 24 | Madelyn Latimer-Hicks | 18 | St Felix Sch | 5:09.60 |